Engine starter



Jan. 13, 1942. I o. F. GOTTLIEB ET AL 22,005

. ENGINE STARTER Original Filed March 31, 19:59 2 Sheets-Sheet i a H /60H 2 Jan. 13, 1942. 0'. F. GOTTLIEB ET AL 22,005

ENGINE STARTER Original Filed March 31, 1939 I 2 Sheets-Sheet 2 I75M/ZUIZ @2755 5775!? Eugene K0/7/5 2 k Reissued Jan. 13, 1942 ENGINESTARTER Oscar F. Gottlieb, Milwaukee, and Ira Milton Jones and ErichEugene .Kohls, Mequon, Wis., assignors to Briggs & Stratton Corporation,Milwaukee, Wis., a corporation of Delaware Original No. 2,201,310, datedMay 21, 1940, Serial No. 265,252, March 31, 1939. Application forreissue August 12, 1941, Serial No. 406,540

18 Claims.

This invention relates to engine starters, .and has as one of itsobjects to provide a more compact and efficient starter mechanism foruse in automobiles.

Another object of this invention is to provide an engine starter inwhich the pinion stop which limits motion of the pinion toward itsoperative position is entirely independentof the drive shaft so as toobviate the necessity for mounting ,a separate stop collar on the shaft.7

Another object of this invention is to provide a structure in which thepinion stop engages an external portion of the pinion or a part carriedthereby so as to permit the smallest possible overall diameter for thepinion and itsdirectly associated parts, to therebyadapt the starter foruse with small engines where space is limited.

Another object of this invention is to provide an engine starter of thetype in which resiliency in the drive from the shaft to the pinion isobtained through the use of a rubber driving element held in compressionand effecting its driving function through frictional contact withadpacent surfaces, wherein adequate means are provided for precludingthe passage of oil and dirt to the rubber element, and wherein this samemeans is utilized to limit the motion of the pinion to operativeposition.

Another object of this invention is to provide an engine starter of thetype described wherein all of the operating mechanism is housed withinan outer barrel-like shell which guards the threaded portions againstcoming in contact with dirt and foreign matter, and generallyimprovesthe operation of the starter and enhances its appearance.

With the above and other objects in view which will appear as thedescription proceeds, this invention resides in the novel construction,combination and arrangement of parts substantially as hereinafterdescribed, and more particularly defined by the appended claims, itbeing understood that such changes in the precise embodiment of theherein disclosed invention may be made as come within the scope of theclaims.

The accompanying drawings illustrate one complete example of thephysical embodiment of the invention constructed in accordance with thebest mode so far devised for the practical application of the principlesthereof, and in which:

Figure 1 is a longitudinal section view through an engine starterconstructed in accordance with this inventionywith theparts shown in thepositions they occupy when the pinion is retracted;

the parts in the positions they assume when the pinion teeth abut thoseof the ring gear;

Figure 3 is a view similar to Figure 1, showin the pinion fully meshedwith the ring gear and about to transmit rotation thereto;

Figure 4 is a cross sectional view through Figure 3 on the plane of theline 4-4; and

Figure 5 is a perspective view of the outer shell per 58.

Referring now particularly to the accompany ing drawings in which likenumerals indicate like parts, the numeral 5 designates an engine ringgear with which a pinion 6 is adapted to be meshed. The pinion 6 ismounted to move longitudinally along the drive shaft I of a startingmotor 8 and to turn therewith, as is customary.

The pinion is propelled to and from its operative position meshing withthe ring gear, as shown in Figure 3, by means of a driving member 9loosely slidable on the shaft and having a threaded connection with thepinion. This threaded connection is formed by external threads H) on thedriving member engaging internal threads II in the bore of a hub I2extending rearwardly from the pinion proper. The hub may be an integralpart of the pinion or it may be formed separately and brazed orotherwise secured thereto.

Rotation is imparted to the driving member from the shaft through aresilient driving connection comprising a collar l3 of rubber or othersuitable material having cubical elasticity and having a highcoeflicient of friction, confined between one face of a flange I4 on thedriving member and one face of a flange 15 which forms part of a collarIS. The collar [6 is mounted on the shaft and secured thereto by a setscrew II.

The flanges l4 and I5 are held against separation beyond a predetermineddistance at which the rubber collar is maintained under an initialdegree 01 compression, by means of an outer barrel-like shell or housingmember I8. This barrel-like shell is preferably formed from a metal tubeand has one end secured to the flange 15 by means of radial outwardlyprojecting lugs IS on the periphery of the flange engaging incorrespondingly positioned slots 20 in the edge of the shell where theyare held by a spring snap ring 2| engaging in a groove 22 the inner wallof the shell. Any other suitable manner of securing the adjacent end ofthe shell to the flange is may be employed, as will be readily apparent.

Medially of its endathe shell is abruptly reduced in diameter to providea shoulder 23 with Figure 2 is a view similar to Figure 1, showing 56which the flange I4 is engageable to limit movement thereof away fromthe flange l5. In this manner, the flanges l4 and are held againstseparation beyond a predetermined distance to at all times maintain therubber collar I3 under an initial degree of compression to insure thetransmission of rotation from the drive shaft to the driving member.

As is well known, upon initial rotation being imparted to the drivingmember, the pinion, because of its inertia, does not turn, but ispropelled longitudinally toward the ring gear 5. If during its forwardpropulsion, it strikes the teeth of the ring gear, the endwiseresiliency of the'rubber collar cushions the impact and build-s upsufficient torque to turn the pinion and effect proper meshing.

When the pinion reaches its fully meshed position, its forwardpropulsion should cease so that the load of the engine can be picked up.Heretofore, the stop to limit forward motion of the pinion was generallya separate collar secured to the shaft inwardly of the ring gear to beengaged by the end of the pinion as it moved to its fully meshedposition. This construction has obvious objections, which are entirelyovercome with the present invention.

In this instance, the forward propulsion of the pinion is limited by theengagement of a collar 24 threaded, welded or otherwise securedto theend of the pinion hub 12 in position to engage "an inturned flange onthe adjacent end of the outer shell. The outer barrel-like shell thusnot only holds the flanges l4 and I5 against separation to maintain therubber ring in compression, but also provides the pinion stop, andbecause it engages the pinion externally, it follows that the diameterof the pinion may be held to a minimum compatible with good design.

Inasmuch as the collar 24 and the flange 25 move relative to each otheras the load of the engine is picked up and the rubber ring twists, ahardened Washer 25 is provided therebetween.

The outer shell-like housing has the additional function of excludingoil and extraneous matter from the rubber ring and the screw threads,even when the pinion is projected to its operative position shown inFigure 3. In other words, the entire driving mechanism for propellingand driving the pinion is housed within the outer shell.

An additional safeguard against ingress of oil and foreign matter intothe interior of the shell is provided by a sealing ring 26 retained in agroove 21 formed in the outer surface of the collar 24 and slidablyengaging the adjacent inper cylindrical surface of the shell.

Accidental or unintentional meshing of the pinion with the ring gear isprevented by a light anti-creep or rebound spring 28 confined betweenthe flange 25 on the shell and a shoulder 25 on the collar 24 formed byhaving its outer surface stepped.

From the foregoing description taken in connection with the accompanyingdrawings, it will be readily apparent that this invention provides anengine starter which is exceptionally compact and which, because itsouter protecting housing completely conceals all of the drivingmechanism,

not only guards against ingress of dirt, oil and grease and otherextraneous matter into the interior of the unit, but also has improvedappearance.

What we claim as our invention is:

1. In an engine starter, the combination of: a drive shaft; anexternally threaded member the shaft to said member comprising anelastical- 1y deformable connector confined between said abutments; andmeans for limiting endwise forward movement of the pinion toward one endof the shaft, said means comprising a shoulder on the exterior of thesleeve at a point remote from the pinion, a part supported fromthe'opposite end portion of the shaft and directed forwardly toward thepinion, and an abutment on said part at all times in juxtaposition tothe sleeve to be engageable with the shoulder thereon.

2. In an engine starter, the combination of: a drive shaft; a pinionmovable endwise along the shaft and rotatable therewith; a sleeve on thepinion provided with an internal screw thread; a member loose on theshaft and externally threaded to fit the threads of the pinion sleeve; aresilient driving connection from the shaft to said member wherebyrotation is imparted from the shaft to the member to automaticallypropel the pinion toward its operative position and thereafterresiliently transmit torque thereto, said driving connection including amember of elastically deformable material under compression betweenabutments on said member and the shaft and at all times lying betweenthe pinion and one end of the shaft; and means for limiting endwisemovement of the pinion toward its' operative position comprising, amember anchored to said end of the shaft and reaching around the drivingconnection to have a part thereof adjacent to said sleeve, an abutmenton said part, and a shoulder on the exterior of the pinion sleeveengageable with said abutment.

3. In an engine starter including: a pinion; an internally threadedsleeve on the pinion; a member having an externally threaded portionthreaded in said pinion sleeve; a member adapted to be secured to adrive shaft; a resilient driving connection between said membersincluding, a rubber element drivingly connected with said members solelythrough frictional engagement; means enclosing said connection toexclude grease and dirt therefrom; and cooperating means on said lastnamed means and the pinion sleeve for limiting endwise movement of thepinion in one direction.

4. An engine starter of the character described comprising: a pinion; athreaded sleeve on the pinion; a driving member having a threadedportion threaded to the pinion sleeve whereby relative rotation betweenthe pinion and said driving member effects relative endwise motionbetween said parts; a member adapted to be fixed to a drive shaft; 9.rubber element confined between said driving member and said last namedmember to provide a resilient driving connection therebetween; an outerhousing receiving support from the member which is attachable to thedrive shaft; means on the outer housing engageable with the drivingmember to limit movement apart between said members and maintain therubber element in compression; and means carried by said housing memberand engageable with a part on the pinion sleeve to limit endwisemovement of the pinion in one direction.

5. An engine starter of the character described pinion connectedthereto; a driving member having a threaded portion threaded to thepinion sleeve whereby relative rotation between the pinion and saiddriving member effects relative endwise motion between said parts; amember adapted to be fixed to a drive shaft; a rubber element confinedbetween said driving member and said last named member to provide aresilient driving connection therebetween; an outer housing receivingsupport from the member'whichisattachable to the drive shaft; means onthe outer housing engageable with the driving member to limit movementapart between said members and maintain the rubber element incompression; an extension on said housing member projecting to- Ward thepinion; and cooperating means on said extension and the connected pinionand sleeve engageable to limit endwise movement of the pinion in onedirection.

6. An engine starter of the character described comprising: a pinion; athreaded sleeve on the pinion; a driving member having a threadedportion threaded to the pinion sleeve whereby relative rotation betweenthe pinion and said driving member effects relative endwise motionbetween said parts; a member adapted to be fixed to a drive shaft; arubber element confined between said driving member and said last namedmember to provide a resilient driving connection (lo-operating means onsaid part and the end of the shell nearest the pinion for limitingrelative endwise motion thereof apart; a member securable to a driveshaft and connected with the shell; and a torsionally resilient drivingconnection from said member to the pinion, said driving connectionincluding internal threads on said part extended from the pinion and anexternally threaded actuator inside the shell and engaging the internalthreads of said pinion part so that the threaded connection is at alltimes covered.

8. An engine starter of the character described comprising: abarrel-like outer shell; means at one end of the shell providing anabutment inside the shell; a pinion; an internally threaded partextended from the pinion into the shell; means on said part engageablewith the abutment to limit outward movement of the pinion with respectto the shell; a member fixed o h hell and bored for reception of a driveshaft to which said member is securable, whereby the shell becomes fixedwith respect to the drive shaft and engagement of the means on thepinion part with the shell abutment constitutes a pinion stop; a drivingconnection from said member to the pinion, said driving connectioncomprising, a driving member inside the shell and having an externalthread engaging the threads of the pinion part; cooperating means on thedriving member and the shell for limiting movement of the driving memberaway from the first named member while permitting movement thereoftoward said first named member; and a rubber element confined betweensaid two members and capable of transmitting rotation'from one to theother.

9 An engine starter of the character described comprising: an outerbarrel-like shell having an instruck flange at one end; a pinion; asleeve extended from the pinion into said end of the shell; a stopcollar secured on the inner end of the sleeve and engageable with theinstruck flange to limit outward movement of the pinion with respect tothe shell; 2, member fixed to the opposite end of the shell, said memberbeing bored for reception of a drive shaft to which said member issecurable; a driving member inside the shell and having a threadedconnection withthe pinion sleeve; and a resilient driving connectionfrom said bored member to the driving member.

10. An engine starter of the character described comprising: an outerbarrel-like shell having an instruck flange at one end; a pinion; asleeve extended from the pinion into said end of the shell; a stopcollar secured on the inner end of the sleeve and engageable with theinstruck flange to limit outward movement of the pinion with respect tothe shell; a member fixed to the opposite end of the shell, said memberbeing bored for reception of a drive shaft to which said memher issecurable; a driving member inside the hell and having a threadedconnection with the pinion sleeve; a resilient driving connection fromsaid bored member to the driving member; and an oil seal between thecollar on th pinion sleeve and the inner face of the shell to retard thepassage of oil and other foreign matter into the interior of the shell.

11. An engine starter of the character described comprising: abarrel-like outer shell; a pinion; a tubular extension on the pinionprojecting into one end of the shell; cooperating means on the shell andsaid tubular extension engageable to limit endwise motion of the tubularextension out of the shell; 3, member fixed to the opposite end of theshell and bored for reception of a drive shaft to which said member issecurable so that the shell becomes fixed with respect to the driveshaft and a driving connection from said member to the pinion forprojecting the pinion into engagement with the flywheel of an engine tobe started and for rotating the pinion after said engagement, part ofsaid driving connection comprising an internal thread on the pinionextension and a screw shaft inside the tubular extension and threadedinto said internal thread so that said part of the driving connection isencircled by the tubular pinion extension and the remainder beingencircled by the shell whereby said tubular pinion extension and theshell cooperate to wholly enclose the driving connection.

12. An engine starter of the character described comprising: abarrel-like outer shell; means providing an abutment at one end of theshell; a pinion; a part extended from the pinion into said end of theshell; means on said part engageable with the abutment to limit outwardmovement of the pinion with respect to the shell; a member fixed to theshell and bored for reception of a drive shaft to which said member issecurable whereby the shell becomes fixed with respect to the driveshaft and engagement of the means on the pinion part with the shellabutment constitutes a pinion stop; a driving member inside the shelland having a threaded connection with said pinion part; and atorsionally resilient driving connection from said bored member to thedriving member inside the shell, comprising an element having cubicalelasticity directly and drivingly engaged with said member and throughwhich the driving force is transmitted.

13. An engine starter of the character described comprising: a pinionhaving a threaded sleeve provided with a stop shoulder; a driving memberhaving a threaded connection with the sleeve and having a flange largerin diameter than the pinion sleeve; a member bored for reception of adrive shaft to which said member is securable; a body of material havingcubical elasticity engaging said bored member and the flange on thedriving member to resiliently transmit torque from the former to thelatter; a cupshaped outer shell having a hole in its bottom wall of asize to permit the pinion and its sleeves to pass therethrough but notthe stop shoulder on the pinion sleeve, and having a shoulder on itsside wall for engagement with the flange on the driving member; andmeans for attaching the open end of the shell to the bored member sothat said shell receives support from the bored member, said shoulder onthe side wall of the shell being so located with relation to the openend of the shell that the attachment of the shell to the bored memberplaces the body of cubical elasticity in a state of compression.

14. In an engine starter: an externally threaded driving member having aflange and bored to receive a drive shaft; a pinion bored to receive theshaft and having an internally member to the driving member; a cup-likeouter shell having a two diameter cylindrical side wall with the steptherebetween providing an abrupt shoulder facing the open end of theshell, said shell encircling the drivin member, pinion sleeve and saidring, and having a hole in its bottom wall of a size to permit thepinion and its sleeve to pass therethrough but insufficient to allowpassage of the stop abutment so that said stop abutment is engageablewith said bottom wall to define the projected position of the pinion,the large open end portion of the shell having the flange on the drivingmember and said elastic ring received therein with the flange engageablewith said shoulder to limit movement of the flange away from the openend of the shell; and means for attaching the open end of the shell tothe bored member so that said shell receives support from the boredmember, and the elastic ring is subjected to pressure between the flangeand said bored member to provide a resilient frictional drivingconnection therebetween.

15. In an engine starter: a drive shaft; a pinion movable along and withthe drive shaft; a driving member movable along and with the driveshaft; a threaded connection between said members so that relativerotation between them effects endwise motion of one with respect to theother, and interference with such relative endwise motion causes saidmembers to revolve in unison; an abutment fixed with respect to theshaft; a torsionally and endwise resilient driving connection betweensaid abutment and the driving member including an elastically deformablebody, said resilient connection becoming increasingly effective totransmit torque with reduction of the distance between the abutment andthe driving member; a stop; and means connecting the stop with theabutment and supporting it in position to limit motion of the pinionmember away from the abutment so that relative rotation between saidmembers continued after endwise motion of the pinion member is arrestedby the stop eflects endwise motion of the driving member toward theabutment to increase the torque transmitting effectiveness of theresilient driving connection.

16. In an engine starter: a drive shaft; a pinion movable along and withthe drive shaft; a driving member movable along and with the driveshaft; a threaded connection between said members so that relativerotation between them effects endwise motion of one with respect to theother, and interference with such relative endwise motion causes saidmembers to revolve in unison; an abutment fixed with respect to theshaft: a torsionally and endwise resilient driving connection betweensaid abutment and the driving member including an elastically deformablebody, said resilient connection becoming increasingly effective totransmit torque with reduction of the distance between the abutment andthe driving member; a barrel-like shell supported from the abutment andencircling the resilient driving connection and at least part of thepinion member; and a stop on said outer shell in position to limitmotion of the pinion member away from the abutment so that relativerotation between said members continued after endwise motion of thepinion members is arrested by the stop, effects motion of the drivingmember toward the abutment to increase the torque transmittingeffectiveness of the resilient driving connection.

17. In an engine starter: a drive shaft; a pinion movable along and withthe drive shaft; a driving member movable alon and with the drive shaft;a threaded connection between said members so that relative rotationbetween them effects endwise motion of one with respect to the other,and interference with such relative endwise motion causes said membersto revolve in unison; an abutment fixed with respect to the shaft; atorsionally and endwise resilient driving connection between saidabutment and the driving member including an elastically deformablebody, said resilient connection becoming increasingly effective totransmit torque with reduction of the distance between the abutment andthe driving member; a barrel-like shell supported from the abutment andencircling the resilient driving connection and at least part of thepinion member; a stop carried by said shell and in position to limitmovement of the driving member away from the abutment to maintain theresilient driving connection operative; and a second stop carried by theshell and in position to limit motion of the pinion member away from theabutment so that relative rotation between said members continued afterendwise motion of the pinion member is arrested by said last-named stopeffects endwise motion of the driving member toward the abutment toincrease the torque transmitting effectiveness of the resilient drivingconnection.

18. In an engine starter: a drive shaft; a pinion movable along and withthe drive shaft; a driving member movable along and with the driveshaft; a threaded connection between said members so that relativerotation between them effects endwise motion of one with respect to theother, and interference with such relative endwise motion causes saidmembers to revolve in unison; an abutment fixed with respect to theshaft; a torsionally and endwise resilient driving connection betweensaid abutment and the driving member including an elastically deformablebody, said resilient connection becoming increasingly efiective totransmit torque with reduction of the distance between the abutment andthe driving member; a two-diameter cylindrical housing member having itslarge diameter end supported from the abutment, the stop between the twodiameters of the housing member providing a stop engageable by a portionof the driving member to limit movement of the driving member away fromthe abutment; and means on the small diameter end portion of the housingmember engageable With part of the pinion member to limit movement ofthe pinion member away from the abutment.

OSCAR F. GOT'ILIEB. IRA MILTON JONES. ERICH EUGENE KOHIS.

